Khalil Hamra, Associated PressEgyptian women line up outside a polling station to cast their votes during a referendum on a disputed constitution drafted by Islamist supporters of President Morsi in Cairo, Egypt, Saturday, Dec. 15, 2012.

CAIRO - Egyptians turned out in large numbers Saturday to begin voting on a contentious draft constitution that has become a referendum on whether President Mohamed Morsi and his Islamist backers are trustworthy guardians of the revolution that ousted strongman Hosni Mubarak nearly two years ago.

Despite weeks of protests that have at times turned into bloody, rock-throwing brawls, voting appeared to be largely peaceful on the first of two Saturdays the balloting is being held. Morsi had empowered the military to protect polling sites and arrest civilians if necessary, but across Cairo soldiers seemed more relaxed than tense as they mingled with police or helped elderly voters up stairs.

Saturday seemed to be a day for debate and, to some extent, reveling in disagreements rather than coming to blows over them.

"I will vote 'no' because some of the articles are not in our best interest," said Nabil Aweys Khalifa, 56, an auto inspector.

"This is your opinion!" said Tamer Ali, 25, a chandelier maker. "The government is good!"

"This is your opinion!" shouted a third man.

"See?" said Khalifa, "Now we have democracy."

Shuffling along in lines that stretched through elite enclaves and others where goats grazed on piled-up trash, voters held spirited discussions on the draft charter, ones that ended with strong yeses and firm nos -- but also more nuanced answers suggesting complicated political identities.

"We are Islamists, but we don't want the constitution to be controlled by one man. We don't want to be brain-washed," said 19-year-old university student Amal Ahmed, who was standing with a group of women in brightly colored scarves in the middle class area of Zeitoun. "This constitution doesn't give us liberty. I can't understand the people who say 'yes.' The people who are well-educated about their rights will say 'no.'"

Across town in the poorer neighborhood of Zeinhom, Said Attia, 62, a security guard who is not an Islamist, said he would nonetheless vote yes on the Islamist-backed charter simply to move the country forward. "All I want is stability," he said. "To see all these divisions, it's not good. I want to try to give Morsi a chance to govern."

But a woman standing in line to vote in the middle class neighborhood of Manial said, "I feel if we say yes to this it will be yes, yes, yes, forever."

The draft charter was passed by an Islamist-dominated assembly after many liberal, Christian and more moderate members walked out saying their concerns about women's rights, free speech and other protections were being ignored. As the previous constitution did, the draft charter establishes Islam as the basis of legislation. But it also enshrines Al Azhar, the respected center of Sunni Muslim scholarship, as a non-binding interpreter of Islamic law, possibly shifting power away from the courts.

Analysts say the constitution leaves some room for interpretation on rights, for instance enshrining a right to free speech but also making it illegal to insult "an individual person." The charter establishes equality between men and women, but contains a provision requiring the state to balance women's rights with their "obligations to family." Muslims, Christians and Jews are explicitly protected, but not minority religions.

Yet many waiting in lines on Saturday were less worried about those specifics than the way that Morsi and his Islamist supporters in the Muslim Brotherhood's Freedom and Justice Party pushed the charter to a vote. On Nov. 22, Morsi issued a constitutional declaration -- since rescinded -- placing his actions beyond judicial review and sending tens of thousands of protesters into the streets calling him a dictator in the making. His move protected the constitution-writing panel from dissolution by the country's highest court and allowed Morsi to call the referendum.

Morsi cast his actions as necessary to overcome a Mubarak-era judiciary that was trying to block Egypt's democratically elected Islamist government from functioning. Opponents saw it as a blatant power grab, and among many who voted no on the draft charter the reason was a lack of trust in a government that would behave in such a manner.

Many saw Saturday's referendum less as a verdict on a document than on the president and his Islamist allies.

"The controversy is not about the constitution itself," said Mohammed al-Gohary, a brotherhood supporter who ran unsuccessfully for parliament last year. "The controversy is about who wrote the constitution -- the Islamists."

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